Generally, an SD-RAN includes an access network and a backhaul network. The backhaul network typically includes multiple fixed-capacity links among base stations, gateways, and data sources. Backhaul links are typically wired links, but can also be wireless. The access network generally includes multiple base stations, which are also referred to as radio nodes, access points, node Bs, or E-node Bs (eNBs). Radio nodes provide service, i.e., access, to the SD-RAN for one or more user equipments (UEs). UEs are sometimes referred to as stations, mobile stations, mobiles, terminals, users, or subscribers.
TE allows the SD-RAN to offer higher network capacity and improved user quality of experience through efficient use of multiple paths between sources and destinations. Additionally, TE gives network operators control over resource usage across the network. To optimize performance of the SD-RAN, the TE problem is generally structured as a balance of flow demand constraints, wired link capacity constraints, and wireless access resource constraints.